DE 39 40 395 A1 describes customary arrangements of wheel bearings. Wheel bearings are either accommodated completely in a wheel carrier or the like, or are suspended on a flange. Tests have shown that the wheel modules with wheel bearings which are as a rule suspended on the wheel carrier via a flange on the outer ring make up a higher weight proportion of the unsprung masses than wheel bearings which are arranged in a hole of a wheel carrier. The construction of the wheel bearings, which are suspended on the wheel carrier and are therefore at least partially self-supporting, and their suspension is to be of particularly rigid design, which results in the increased weight proportion in comparison with the wheel bearings which are accommodated in holes. DE 39 40 395 A1 thus describes a wheel bearing having an outer ring, rolling bodies and having two inner rings, whose outer ring has a radial flange axially between the end sides and away from the end sides. The wheel bearing is suspended on the wheel carrier via the flange. The wheel bearing is thus fixed axially and radially on the wheel carrier via the flange.
A hollow cylindrical section of the outer ring which adjoins the flange axially is seated moreover in a hole of the carrier, with the result that the outer ring bears against the carrier axially by means of the flange and partially radially at least with the section. The outer ring is loaded highly in the channel at the transition from the flange to the section. The channel is therefore usually rounded with a radius, by means of which notch stresses in the channel are to be reduced. However, the stresses which prevail in the channel are still excessively high, especially as the outer ring also bears against the carrier via the channel and additional stresses are built up under load in the flange as a result.
DE 39 40 395 A1 additionally describes a wheel bearing which is accommodated completely in a hole of a wheel carrier. The outer ring is of solid configuration and manufactured by material removing machining. A press fit which is customary in the roller bearing field secures the outer ring in the hole. In the case of loading of the wheel bearing during driving operation, the outer ring tends to move axially despite the press fit. To counteract this, the outer ring is secured in the hole with a securing ring on one side and is supported on an inner shoulder on the other side. The preparation of a bearing seat of this type is complicated, as the shoulder makes material removing machining difficult in the axial direction. Furthermore, the notch is to be introduced for the securing ring. The press fit also often becomes loose during driving operation, with the result that notches are produced on the carrier or on the outer ring by wear and/or the known and undesirable creaking noises occur as a result of the micromovements of the outer ring with respect to the carrier. Seats of this type also become loose if the wheel carrier is manufactured from a different material than the outer ring. This affects, for example, arrangements, in which the wheel carrier is made from an aluminum alloy and the outer ring is made from steel. The different material characteristic values, such as modulus of elasticity and coefficient of thermal expansion, of the wheel carrier with respect to the outer ring have a disadvantageous effect on a permanent firm fit of the outer ring in the wheel carrier.
Wheel bearing units (U.S. Pat. No. 3,757,883) are known, in which the inner ring and/or the outer ring are/is cold formed from sheet metal. The outer rings are of hollow cylindrical configuration about the rotational axis of the wheel bearing unit and in each case have two raceways for rolling bodies. On its side which faces away from the raceways, the outer ring has a radially outwardly oriented flange, with which the wheel bearing is fixed on the vehicle side. The inner ring is provided with a likewise outwardly oriented connecting flange as hub, to which the brake disk and the wheel of a vehicle which is driven via the inner outer ring are fastened. The raceways are introduced into the respective bearing ring in a radially at least partially recessed manner and are separated from one another by shoulders. The raceways of the angular contact ball bearing run out at the shoulders which protrude radially from the raceways.
The outer rings which are manufactured without cutting from sheet metal are of particularly solid configuration, as the bearing is fastened freely to the vehicle at one radial flange of the outer ring. The weight of the rings has a disadvantageous effect on the total balance of the unsprung masses on the vehicle. In addition, the outer rings are relatively rigid on account of their thick walls, with the result that elastic compression of the outer rings, which is desired in some circumstances, is ruled out. A bearing arrangement of this type can be prestressed without play only with extreme difficulty, on account of the high rigidity of the outer rings.